There's a difference between Redemption and Atonement.
And Good and Evil being Verbs or Nouns/Adjetives.
People can recognize they have done wrong, and choose to be better. Their victims do not owe them forgiveness. They are not owed forgiveness. The harm they've done still matters.
But if you don't accept surrender, you don't allow your enemy to give up, you allow them only to double down. The Blood they would have stopped spilling is now on your hands.
Abusers have (karmic) debts to pay. Their victims may want nothing more to do with them. Their victims owe them nothing, not forgiveness, not accepting debt payments. They can reach out to people who are where they were, and speak on a level others can't. As peers, who've walked that path, and taken those actions, and offer a different choice. With introspection they can explain where the abuse came from within them, what lead them to the place where it was 'normal', and/or 'acceptable' and/or 'necessary', and help others avoid or dismantle those environments.
The Dead pay no Debts. And when you don't accept surrender, you ensure the enemy dies fighting, dies causing More Harm. Your purity isn't worth the blood on both your hands. Let them Stop being Evil.
Redemption is based on the word used for Purchasing Slaves. It, as a concept, is 'Evil no longer owns your soul'. Nothing more, nothing less.
Atonement is, to my understanding, 'I have done wrong, and it is my responsibility to make it right. This may not be possible, but I have to try anyway. I have to make up for what I've done. To Balance the Scales. Some things cannot be forgiven, and cannot be undone, but still, you have to try to balance the scales. You may never know if you succeed. But trying matters.'